1. Field of the Invention
The present invention relates to a communication apparatus for detecting a signal from a communication network.
2. Description of the Related Art
Facsimile apparatuses for detecting various kinds of tone signals and control signals from a network are present as conventional apparatuses of this kind. Some conventional facsimile apparatuses have an automatic calling function, an automatic call-receiving function, a function of connecting a call to a message-receiving telephone set, and the like, and perform desired processing by identifying various kinds of tone signals transmitted from a switchboard, a voice or various kinds of control signals transmitted from an operator of a communication partner or a communication apparatus of the communication partner, respectively, and a voice response message transmitted from a message-receiving telephone set or according to a voice response function provided in the facsimile apparatus, and the like. In such conventional apparatuses having known signal formats, information (parameters) for detecting a signal, such as a frequency, an on-time and an off-time, and the like, is set in consideration of variations in the characteristics of a communication network, and a signal having parameters within a detection range is monitored.
In the conventional facsimile apparatuses, since a detection frequency, and an on-time and an off-time of a signal are set in consideration of variations in the characteristics of a communication partner""s apparatus and the characteristics of a communication network, a large margin is set for an actual signal. Accordingly, a voice transmitted from an operator of a communication partner, or a communication parnter""s apparatus, a voice response message transmitted from a message-receiving telephone set connected to the facsimile apparatus, or according to a voice response function of the facsimile apparatus, or the like is erroneously detected as a tone signal or a control signal to be detected, resulting in a misoperation of the apparatus.
The present invention has been made in consideration of the above-described problems.
It is an object of the present invention to provide an improved communication apparatus.
It is another object of the present invention to provide a communication apparatus which can perform signal detection corresponding to variations in the characteristics of a communication apparatus of a communication partner or in the characteristics of a communication network when detecting a signal from the communication network.
According to one aspect, the present invention which achieves these objectives relates to a communication apparatus for detecting a signal from a communication network. The apparatus includes detection means for detecting a signal of one period in accordance with preset detection parameters, and changing means for changing the detection parameters based on the signal detected by the detection means, the detection means then detecting a signal of one period in accordance with the changed detection parameters.
According to another aspect, the present invention which achieves these objectives relates to a communication method for detecting a signal from a communication network. The method includes the steps of detecting a signal of one period in accordance with preset detection parameters, changing the preset detection parameters based on the detected signal, and detecting a signal of one period in accordance with the changed detection parameters.
The foregoing and other objects, advantages and features of the present invention will become more apparent from the following detailed description of the preferred embodiment taken in conjunction with the accompanying drawings.